3 Jan
2021
3 Jan
'21
4:08 p.m.
On Sun, 3 Jan 2021 at 03:53, Boris Gimbarzevsky <boris at summitclinic.com> wrote:
Ran into 68000 processor for
first time in 1986 when my father bought a 512 K
Mac and couldn't believe performance of this CPU
It is odd. I had read of it, of course, but for me the revelation was
getting an Acorn Archimedes in 1989, with an 8MHz ARM2, and seeing it
blast past benchmarks of ~8MHz 68K machines such as the Amiga 500 or
Atari 512 ST. It was about 4x faster, I believe.
For me -- being a bit too young for the early days of the 68K family
-- it was not a performance chip, but more about its ability to have
lots of flat memory, unlike the crippled Intel chips that IBM used.
Weird that Rod Coleman had 68000
instruction set associated with IBM 370 whereas
to me it was very PDP-11 like
I've heard that before, yes,. and never the IBM comparison.
I suppose it is a matter of what you're more familiar with.
Thanks for the link as didn't realize 68000 was
used for home systems before I ran into Mac.
Sinclair's QL used a 68008 and was launched some weeks before the Mac.
Of course Apple's own Lisa was before the Mac, too.
Very soon after came the Amiga and ST -- the "Jackintosh", "power
without the price."
--
Liam Proven ? Profile: https://about.me/liamproven
Email: lproven at cix.co.uk ? gMail/gTalk/gHangouts: lproven at gmail.com
Twitter/Facebook/LinkedIn/Flickr: lproven ? Skype: liamproven
UK: +44 7939-087884 ? ?R (+ WhatsApp/Telegram/Signal): +420 702 829 053
4 Jan
4 Jan
6:35 a.m.
On 2021-01-03 19:08, Liam Proven via cctalk wrote:
On Sun, 3 Jan 2021 at 03:53, Boris Gimbarzevsky
<boris at summitclinic.com> wrote:
I guess we have to be careful, comparing machines & CPUs.
68000 came out as a CPU in 1980/1981 (available on the market (?))
You're comparing it to a ARM2 machine of 1987, where Motorola had the
newer 68020, and 68030 by than ...
Ran into 68000 processor for
first time in 1986 when my father bought a 512 K
Mac and couldn't believe performance of this CPU
It is odd. I had read of it, of course, but for me the revelation was
getting an Acorn Archimedes in 1989, with an 8MHz ARM2, and seeing it
blast past benchmarks of ~8MHz 68K machines such as the Amiga 500 or
Atari 512 ST. It was about 4x faster, I believe.
7:38 a.m.
On Mon, 4 Jan 2021 at 15:35, emanuel stiebler <emu at e-bbes.com> wrote:
I guess we have to be careful, comparing machines & CPUs.
68000 came out as a CPU in 1980/1981 (available on the market (?))
You're comparing it to a ARM2 machine of 1987, where Motorola had the
newer 68020, and 68030 by than ...
That's a fair objection. :-)
I suppose that the 68K only trickled down to the home/consumer market
after about 5 years. The original Mac was circa $2.5K and the Lisa was
around $10K -- *not* home computer prices for most people, even in the
USA.
The Sinclair QL was arguably the first affordable mass-market 68K box,
and it used the somewhat crippled 68008 and 8-bit RAM to keep costs
down.
Before the Mac, I suppose that, as Cameron points out, the accurate
comparison was with standalone multi-user machines such as the Sage
and Alpha Micro. Desktop minicomputers, really.
These were fading from the market when I started my first job in 1988.
The only ones I personally worked on were Jarograte Sprite machines --
of which barely a trace remains on the WWW now, sadly. I'd like to
know more about Jarogate and their products -- most of what I did was
helping migrate stuff _off_ them onto either 386s running SCO Xenix,
or small PC LANs.
--
Liam Proven ? Profile: https://about.me/liamproven
Email: lproven at cix.co.uk ? gMail/gTalk/gHangouts: lproven at gmail.com
Twitter/Facebook/LinkedIn/Flickr: lproven ? Skype: liamproven
UK: +44 7939-087884 ? ?R (+ WhatsApp/Telegram/Signal): +420 702 829 053
8:42 a.m.
I suppose that the 68K only trickled down to the
home/consumer market
after about 5 years. The original Mac was circa $2.5K and the Lisa was
around $10K -- *not* home computer prices for most people, even in the
USA.
The Sinclair QL was arguably the first affordable mass-market 68K box,
and it used the somewhat crippled 68008 and 8-bit RAM to keep costs
down.
Before the Mac, I suppose that, as Cameron points out, the accurate
comparison was with standalone multi-user machines such as the Sage
and Alpha Micro. Desktop minicomputers, really.
Agreed.
A fully provisioned IBM PC / XT in 1981-4 was pretty expensive too, that's
why 8-bit machines continued to sell well into the later 80's. 16-bit was
overkill for most home needs. Apple would not have survived the 80's
without their 8-bit machine sales, and Commodore, Atari, Tandy....
Bill
9:26 a.m.
On Mon, 4 Jan 2021 at 17:42, Bill Degnan <billdegnan at gmail.com> wrote:
Agreed.
A fully provisioned IBM PC / XT in 1981-4 was pretty expensive too, that's why 8-bit
machines continued to sell well into the later 80's. 16-bit was overkill for most
home needs. Apple would not have survived the 80's without their 8-bit machine sales,
and Commodore, Atari, Tandy....
Definitely true.
And one thing that interests me is the double factoid:
[1] The companies that threw away their 8-bit line and did something
totally new for their 16-bit lines generally did better, and attempts
at backwards-compatibility failed
_except_
[2] For Intel/MICROS~1, who somehow managed to smoothly transition
from 8/16 ? true 16-bit ? 32-bit ? 64-bit ? multi-CPU ?
multi-core/multi-CPU, across multiple expansion buses, memory
architectures and more...
--
Liam Proven ? Profile: https://about.me/liamproven
Email: lproven at cix.co.uk ? gMail/gTalk/gHangouts: lproven at gmail.com
Twitter/Facebook/LinkedIn/Flickr: lproven ? Skype: liamproven
UK: +44 7939-087884 ? ?R (+ WhatsApp/Telegram/Signal): +420 702 829 053
9:40 a.m.
On 1/4/2021 10:26 AM, Liam Proven via cctalk wrote:
On Mon, 4 Jan 2021 at 17:42, Bill Degnan
<billdegnan at gmail.com> wrote:
I say IBM is the winner here. IBM 7030 Stretch gave IBM a design based
on 8 bit bytes, that followed with the IBM 360. Salesman love bytes
because now your 4K of memory (36/48 bits) is 32KB of IBM memory and
time sharing because you can FAKE the need for real memory.
Ben Fan of 36 bits but not the PDP 10.
Agreed.
A fully provisioned IBM PC / XT in 1981-4 was pretty expensive too, that's why 8-bit
machines continued to sell well into the later 80's. 16-bit was overkill for most
home needs. Apple would not have survived the 80's without their 8-bit machine sales,
and Commodore, Atari, Tandy....
Definitely true.
And one thing that interests me is the double factoid:
[1] The companies that threw away their 8-bit line and did something
totally new for their 16-bit lines generally did better, and attempts
at backwards-compatibility failed
_except_
[2] For Intel/MICROS~1, who somehow managed to smoothly transition
from 8/16 ? true 16-bit ? 32-bit ? 64-bit ? multi-CPU ?
multi-core/multi-CPU, across multiple expansion buses, memory
architectures and more...
11:29 a.m.
m?n 2021-01-04 klockan 16:38 +0100 skrev Liam Proven via cctalk:
The Sinclair QL was arguably the first affordable mass-market 68K
box,
and it used the somewhat crippled 68008 and 8-bit RAM to keep costs
down.
The veird machine is the Luxor ABC 1600 computer.
It was a test from them together with a consulting firm to design and
sell a UNIX based system (an version of Sys III if i'm not wrong) using
an MC 68008 but with a A4 portrait monitor.
The weird thing: why did they try to use a crippled processor (but
it gave them cheaper peripherals)
but a fairly expensive graphical subsystem with monitor....
Have and Have nots...
See http://www.datormuseum.se/computers/luxor/abc1600
and yes it is Mattis Lind together with his father Rune who run this
little museum.
11:35 a.m.
New subject: personal history of personal computers
On Mon, 4 Jan 2021, Liam Proven via cctalk wrote:
I suppose that the 68K only trickled down to the
home/consumer market
after about 5 years. The original Mac was circa $2.5K and the Lisa was
around $10K -- *not* home computer prices for most people, even in the
USA.
And yet, . . .
I remember an Apple Lisa ad that showed a toddler playing with it on the
living room rug. (Probably rolling the mouse around and making "VROOM!
VROOM!" noises, pretending that it was a car)
Similar ads for Macintosh and IBM PC.
The marketing people TRIED to portray them as home computers.
You can place an infant on a Cray Couch; that still doesn't make that a
home computer.
YES, a fully loaded IBM PC, complete with buying a full suite of software
from IBM WAS comparable in price to a complete
Macintosh. However, the
ENTRY point was lower. You could buy a minimal machine
and expand it
yourself.
My first TRS-80 was $400, because I used my own monitor and cassette. And
then later, my own disk drives.
My first 5150 was less than $1500, because I used my own monitor, memory,
disk drives, and printer.
Segmented memory was a kludge, and not the only kludge. Remember that a
DMA transfer could not straddle a 64K boundary! Many programs, even
MS-DOS, failed to take that into account adequately! It was not hard to
handle that particular one - just test for it, and rearrange your larger
data structures accordingly.
BUT, by building through a series of kludges, it was truly trivial to port
software as the machines progressed. At time of release, IBM had
pre-planned to have VisiCalc and Easy-Writer.
Porting Wordstar to the PC was fast and easy; it took them longer to edit
the documentation (using a word processor?).
Porting SuperCalc (a major VisiClone) was very quick.
The opposite approach, of NO KLUDGES, resulted in much better product.
But, it took longer, AND, it meant a serious delay for software, since
any low-level software would then also need to be rewritten from scratch.
To avoid the PR nightmare of a machine with no software, Apple decided
that when the Macintosh would be released, it would come with four
significant software packages. It ended up being scaled back to the four
being Mac-Write, Mac-Paint, Mac-Write, and Mac-Paint. But, it came with
some usable software.
It took a long time before after-market software, even spreadsheets, were
available for the Macintosh.
--
Grumpy Ol' Fred cisin at xenosoft.com
1:31 p.m.
New subject: personal history of personal computers
There was a little known 68K machine. It was the Canon Cat. Although, it was generally not
intended as a development machine, in its short life, several applications were
developed.
It was primarily sold as a word processor ( quite powerful one at that ). It had Forth
running under the word processor. One could do both assembly and other things once one
understood how to access the Forth.
If you should ever get one, don't use the disk drive until you talk to me.
It has a common problem that if you don't understand it will destroy the drive.
Dwight
________________________________
From: cctalk <cctalk-bounces at classiccmp.org> on behalf of Fred Cisin via cctalk
<cctalk at classiccmp.org>
Sent: Monday, January 4, 2021 11:35 AM
To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org>
Subject: Re: personal history of personal computers
On Mon, 4 Jan 2021, Liam Proven via cctalk wrote:
I suppose that the 68K only trickled down to the
home/consumer market
after about 5 years. The original Mac was circa $2.5K and the Lisa was
around $10K -- *not* home computer prices for most people, even in the
USA.
And yet, . . .
I remember an Apple Lisa ad that showed a toddler playing with it on the
living room rug. (Probably rolling the mouse around and making "VROOM!
VROOM!" noises, pretending that it was a car)
Similar ads for Macintosh and IBM PC.
The marketing people TRIED to portray them as home computers.
You can place an infant on a Cray Couch; that still doesn't make that a
home computer.
YES, a fully loaded IBM PC, complete with buying a full suite of software
from IBM WAS comparable in price to a complete
Macintosh. However, the
ENTRY point was lower. You could buy a minimal machine
and expand it
yourself.
My first TRS-80 was $400, because I used my own monitor and cassette. And
then later, my own disk drives.
My first 5150 was less than $1500, because I used my own monitor, memory,
disk drives, and printer.
Segmented memory was a kludge, and not the only kludge. Remember that a
DMA transfer could not straddle a 64K boundary! Many programs, even
MS-DOS, failed to take that into account adequately! It was not hard to
handle that particular one - just test for it, and rearrange your larger
data structures accordingly.
BUT, by building through a series of kludges, it was truly trivial to port
software as the machines progressed. At time of release, IBM had
pre-planned to have VisiCalc and Easy-Writer.
Porting Wordstar to the PC was fast and easy; it took them longer to edit
the documentation (using a word processor?).
Porting SuperCalc (a major VisiClone) was very quick.
The opposite approach, of NO KLUDGES, resulted in much better product.
But, it took longer, AND, it meant a serious delay for software, since
any low-level software would then also need to be rewritten from scratch.
To avoid the PR nightmare of a machine with no software, Apple decided
that when the Macintosh would be released, it would come with four
significant software packages. It ended up being scaled back to the four
being Mac-Write, Mac-Paint, Mac-Write, and Mac-Paint. But, it came with
some usable software.
It took a long time before after-market software, even spreadsheets, were
available for the Macintosh.
--
Grumpy Ol' Fred cisin at xenosoft.com
1:38 p.m.
New subject: personal history of personal computers
Andy Molloy had a Canon Cat at VCF East in 2006. Unfortunately, it smoked.
http://q7.neurotica.com/Oldtech/VCF-East2006/dscn4151-f.jpg
On Mon, 4 Jan 2021, dwight via cctalk wrote:
There was a little known 68K machine. It was the Canon
Cat. Although, it was generally not intended as a development machine, in its short life,
several applications were developed.
It was primarily sold as a word processor ( quite powerful one at that ). It had Forth
running under the word processor. One could do both assembly and other things once one
understood how to access the Forth.
If you should ever get one, don't use the disk drive until you talk to me.
It has a common problem that if you don't understand it will destroy the drive.
Dwight
________________________________
From: cctalk <cctalk-bounces at classiccmp.org> on behalf of Fred Cisin via cctalk
<cctalk at classiccmp.org>
Sent: Monday, January 4, 2021 11:35 AM
To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org>
Subject: Re: personal history of personal computers
On Mon, 4 Jan 2021, Liam Proven via cctalk wrote:
Mike Loewen mloewen at cpumagic.scol.pa.us
Old Technology http://q7.neurotica.com/Oldtech/
I suppose that the 68K only trickled down to the
home/consumer market
after about 5 years. The original Mac was circa $2.5K and the Lisa was
around $10K -- *not* home computer prices for most people, even in the
USA.
And yet, . . .
I remember an Apple Lisa ad that showed a toddler playing with it on the
living room rug. (Probably rolling the mouse around and making "VROOM!
VROOM!" noises, pretending that it was a car)
Similar ads for Macintosh and IBM PC.
The marketing people TRIED to portray them as home computers.
You can place an infant on a Cray Couch; that still doesn't make that a
home computer.
YES, a fully loaded IBM PC, complete with buying a full suite of software
from IBM WAS comparable in price to a complete Macintosh. However, the
ENTRY point was lower. You could buy a minimal machine and expand it
yourself.
My first TRS-80 was $400, because I used my own monitor and cassette. And
then later, my own disk drives.
My first 5150 was less than $1500, because I used my own monitor, memory,
disk drives, and printer.
Segmented memory was a kludge, and not the only kludge. Remember that a
DMA transfer could not straddle a 64K boundary! Many programs, even
MS-DOS, failed to take that into account adequately! It was not hard to
handle that particular one - just test for it, and rearrange your larger
data structures accordingly.
BUT, by building through a series of kludges, it was truly trivial to port
software as the machines progressed. At time of release, IBM had
pre-planned to have VisiCalc and Easy-Writer.
Porting Wordstar to the PC was fast and easy; it took them longer to edit
the documentation (using a word processor?).
Porting SuperCalc (a major VisiClone) was very quick.
The opposite approach, of NO KLUDGES, resulted in much better product.
But, it took longer, AND, it meant a serious delay for software, since
any low-level software would then also need to be rewritten from scratch.
To avoid the PR nightmare of a machine with no software, Apple decided
that when the Macintosh would be released, it would come with four
significant software packages. It ended up being scaled back to the four
being Mac-Write, Mac-Paint, Mac-Write, and Mac-Paint. But, it came with
some usable software.
It took a long time before after-market software, even spreadsheets, were
available for the Macintosh.
--
Grumpy Ol' Fred cisin at xenosoft.com
1:43 p.m.
New subject: personal history of personal computers
On 2021-01-04 4:38 p.m., Mike Loewen via cctalk wrote:
?? Andy Molloy had a Canon Cat at VCF East in 2006. Unfortunately, it
smoked.
http://q7.neurotica.com/Oldtech/VCF-East2006/dscn4151-f.jpg
... there's one on ebay now FWIW.
--Toby
1:43 p.m.
New subject: personal history of personal computers
On Mon, Jan 4, 2021, 1:38 PM Mike Loewen via cctalk <cctalk at classiccmp.org>
wrote:
Andy Molloy had a Canon Cat at VCF East in 2006. Unfortunately, it
smoked.
http://q7.neurotica.com/Oldtech/VCF-East2006/dscn4151-f.jpg
Someone could buy one from Jack and fix it up eBay 324441040706.
1:42 p.m.
New subject: personal history of personal computers
On Mon, 4 Jan 2021, dwight wrote:
There was a little known 68K machine. It was the Canon
Cat. Although, it was generally not intended as a development machine, in its short life,
several applications were developed.
It was primarily sold as a word processor ( quite powerful one at that ). It had Forth
running under the word processor. One could do both assembly and other things once one
understood how to access the Forth.
If you should ever get one, don't use the disk drive until you talk to me.
It has a common problem that if you don't understand it will destroy the drive.
Dwight
That was an amazing machine.
Raskin was an amazing character. He was responsible for many innovations
and design decisions throughout the industry.
(and, I almost ended up getting his electric minivan)
I had a running argument with Jef. If you have a room full of a variety
of disks, including multiple MFM formats AND GCR, the default when it
couldn't read a disk should NOT be to FORMAT it.
--
Grumpy Ol' Fred cisin at xenosoft.com
2:04 p.m.
New subject: personal history of personal computers
On the issue of the Cat re-formatting disks that it couldn't read, my
suggestion was that they should add enough circuitry that it could
recognize the existence of FM, MFM, and GCR formats.
Then, it could say, "This disk appears to already be formatted for a
different kind of machine. Would you like to erase it and reformat for
this machine?"
I offered to provide data, so that if it could also identify recording
format, number of sides formatted, and maybe even bytes per sector and
sectors per track, it could expand the massge to include "The following
machines are some of the possibilities of what it is formatted for:"
. . . and, of course, the ultimate would be to implement some other file
systems, so that it could access what was on the disk.
--
Grumpy Ol' Fred cisin at xenosoft.com
3:19 p.m.
New subject: personal history of personal computers
There was a little known 68K machine. It was the Canon
Cat.
I love the form factor of my Cat. Wish it was easier to "do things" with it
though.
If you should ever get one, don't use the disk
drive until you talk to me.
Don't leave us in suspense! However, mine seems to be fine.
--
------------------------------------ personal: http://www.cameronkaiser.com/ --
Cameron Kaiser * Floodgap Systems * www.floodgap.com * ckaiser at floodgap.com
-- Why is it you can only trust short, dumpy spies? -- Hogan, "Hogan's
Heroes"
4:53 p.m.
New subject: personal history of personal computers
Need to grease/lube it periodically
On Mon, Jan 4, 2021, 6:20 PM Cameron Kaiser via cctalk <
cctalk at classiccmp.org> wrote:
There was a
little known 68K machine. It was the Canon Cat.
I love the form factor of my Cat. Wish it was easier to "do things" with it
though.
If you should ever get one, don't use the
disk drive until you talk to
me.
Don't leave us in suspense! However, mine seems to be fine.
--
------------------------------------ personal:
http://www.cameronkaiser.com/ --
Cameron Kaiser * Floodgap Systems * www.floodgap.com *
ckaiser at floodgap.com
-- Why is it you can only trust short, dumpy spies? -- Hogan, "Hogan's
Heroes"
5:39 p.m.
New subject: personal history of personal computers
On Mon, 2021-01-04 at 19:53 -0500, Bill Degnan via cctalk wrote:
Need to grease/lube it periodically
Is it English? I understand the English stopped building computers
because they couldn't figure out how to make them leak oil.
On Mon, Jan 4, 2021, 6:20 PM Cameron Kaiser via cctalk
<
cctalk at classiccmp.org> wrote:
> > There was a little known 68K machine. It was the Canon Cat.
>
> I love the form factor of my Cat. Wish it was easier to "do things"
> with itthough.
> > If you should ever get one, don't use the disk drive until you
> > talk to
> me.
> Don't leave us in suspense! However, mine seems to be fine.
> -------------------------------------- personal:
> http://www.cameronkaiser.com/ -- Cameron Kaiser * Floodgap Systems
> * www.floodgap.com *ckaiser at floodgap.com
> -- Why is it you can only trust short, dumpy spies? -- Hogan,
> "Hogan'sHeroes"
4 Jan
4 Jan
7:17 p.m.
New subject: personal history of personal computers
there is a sing rail that guide the head. At the back of the rail is a small nylon tab
that holds it in place. The way they mad it, it is over stressed and will have failed.
This means the rail is not held down securely. Eventually the rail will pop up, not being
held down securely any more. You will find the first indication is that the disk will not
eject properly. the temptation is to pull it out, thinking it is just a sticky eject, but
that isn't the problem. It is catching on the head. Eventually it will catch really
well and you'll rip the head of the mount. At this point the disk can not be repaired.
It is an unusual drive, being single sided and requiring the DriveReady signal. It also
has a build in cable instead of the standard edge connector and power connector. Most of
the new drive no longer have the DriveReady signal, even as an option.
One can make changes to the software if you know how to use the data or sector pulse as a
DriveReady.
This usually requires a one shot to hold the pulse for the software to recognize the
pulse.
There are several things on can do with it. With a few simple modifications, one can
increase the RAM ( mostly just installing ) but for text you can't have more than
100K. It is possible to use a newer version of the software that includes the assembler.
One of the more frustrating things is that it normally only has drivers for Cannon
printers, with the excepting that it will also do the FX80 compatible printers. It is not
too hard to write one's own printer drive and substitute it for one of the printer
drivers. This is normally done such that it will use a portion of the disk and overlay in
RAM for one of the drivers. I've done this to use a HP pcl5 type printer. ( I
don't support all of the funny characters though ).
You can write your code in the editor and compile it into RAM. As an extension, it can be
saved on onto the disk such that it is available the next time you use that disk.
As I recall, the official software is 1.73. The new code with the assembler is 2.40 (
never released ). I have a copy of that version.
Anyway, the RAM can be expanded by putting chips into the sockets and adding socket to the
last row. I've expanded the RAM even more by adding a large CMOS RAM to an unused
address decoded area. One does have to make a minor hack and add a gate to deal with the
high/low byte 68000. I just mount a IC dead bug but one does have to lift a couple leads
of the 68000.
I use the extra RAM to recompile the Forth and editor software, to blow as an EPROM. I can
compile it to run in the RAM space or the EPROM area. This allows me to test it first
before changing the constant for the offset.
Dwight
________________________________
From: cctalk <cctalk-bounces at classiccmp.org> on behalf of Cameron Kaiser via
cctalk <cctalk at classiccmp.org>
Sent: Monday, January 4, 2021 3:19 PM
To: cctalk at classiccmp.org <cctalk at classiccmp.org>
Subject: Re: personal history of personal computers
There was a little known 68K machine. It was the Canon
Cat.
I love the form factor of my Cat. Wish it was easier to "do things" with it
though.
If you should ever get one, don't use the disk
drive until you talk to me.
Don't leave us in suspense! However, mine seems to be fine.
--
------------------------------------ personal: http://www.cameronkaiser.com/ --
Cameron Kaiser * Floodgap Systems * www.floodgap.com<http://www.floodgap.com> *
ckaiser at floodgap.com
-- Why is it you can only trust short, dumpy spies? -- Hogan, "Hogan's
Heroes"
24 Jan
24 Jan
3:13 p.m.
New subject: personal history of personal computers
On Jan 4, 2021, at 1:31 PM, dwight via cctalk <cctalk at classiccmp.org> wrote:
There was a little known 68K machine. It was the Canon Cat. Although, it was generally
not intended as a development machine, in its short life, several applications were
developed.
It was primarily sold as a word processor ( quite powerful one at that ). It had Forth
running under the word processor. One could do both assembly and other things once one
understood how to access the Forth.
If you should ever get one, don't use the disk drive until you talk to me.
It has a common problem that if you don't understand it will destroy the drive.
What happens if it's not possible to talk to you? Can you write up just what the deal
is with the drive, so that everyone can learn?
-- Chris
3:16 p.m.
New subject: personal history of personal computers
On Jan 24, 2021, at 3:13 PM, Chris Hanson via cctalk <cctalk at classiccmp.org>
wrote:
What happens if it's not possible to talk to you?
Can you write up just what the deal is with the drive, so that everyone can learn?
And now I see that you've done so?thank you!
-- Chris
5:16 p.m.
New subject: personal history of personal computers
I believe I describe this. There is a nylon clip that holds the guide rail for the head
assembly. This nylon was over stressed. Every machine that I've seen, the nylon had
hardened and cracked. It allows the rail to float. What happens is that the rail lifts up.
When ejecting the floppy the plastic cover catches on the head. One that is removing the
disk is likely to assume that it is just the eject hanging a little and they pull the disk
out. This rips the head from the mount, destroying the drive.
I saw a Cat on ebay and asked the seller to pass on my email to the buyer, to tell him to
not force the disk from the drive, because it would damage the head. I did not get to him
soon enough. He had already damaged the head. He said he'd wish he'd read my
message earlier.
This is such a common failure that I continue to warn people about it as often as I can. I
also did some repair for a fellow that used Cats in his business. I was only able to fix 2
of 5 drives. Luckily these had a head mount was just bent and not ripped off.
The desired fix is to open the disk drive and replace the nylon piece with something to
hold it in place. I used a piece of plastic but several use a small dab of JB Weld. There
is little reason to ever remove the rail.
The drive use is driven through a soldered on ribbon cable, unlike most such HD drives.
Because of software, it requires the DriveReady signal. Most drives no longer have this.
It can be created with the retriggerable oneshot, on an adapter cable.
I hope that covers it. Disassembly of the drive is a little trick to get at the rail but
anyone with some mechanical ability can do it. Do look at how the eject works before
disassembling.
Dwight
________________________________
From: Chris Hanson <cmhanson at eschatologist.net>
Sent: Sunday, January 24, 2021 3:13 PM
To: dwight <dkelvey at hotmail.com>; General Discussion: On-Topic and Off-Topic
Posts <cctalk at classiccmp.org>
Cc: Fred Cisin <cisin at xenosoft.com>
Subject: Re: personal history of personal computers
On Jan 4, 2021, at 1:31 PM, dwight via cctalk <cctalk at classiccmp.org> wrote:
There was a little known 68K machine. It was the Canon Cat. Although, it was generally
not intended as a development machine, in its short life, several applications were
developed.
It was primarily sold as a word processor ( quite powerful one at that ). It had Forth
running under the word processor. One could do both assembly and other things once one
understood how to access the Forth.
If you should ever get one, don't use the disk drive until you talk to me.
It has a common problem that if you don't understand it will destroy the drive.
What happens if it's not possible to talk to you? Can you write up just what the deal
is with the drive, so that everyone can learn?
-- Chris
5:19 p.m.
New subject: personal history of personal computers
I believe Jack Rubin has taken pictures of his repair. He frequents this message board.
Dwight
________________________________
From: cctalk <cctalk-bounces at classiccmp.org> on behalf of dwight via cctalk
<cctalk at classiccmp.org>
Sent: Sunday, January 24, 2021 5:16 PM
To: Chris Hanson <cmhanson at eschatologist.net>; General Discussion: On-Topic and
Off-Topic Posts <cctalk at classiccmp.org>
Subject: Re: personal history of personal computers
I believe I describe this. There is a nylon clip that holds the guide rail for the head
assembly. This nylon was over stressed. Every machine that I've seen, the nylon had
hardened and cracked. It allows the rail to float. What happens is that the rail lifts up.
When ejecting the floppy the plastic cover catches on the head. One that is removing the
disk is likely to assume that it is just the eject hanging a little and they pull the disk
out. This rips the head from the mount, destroying the drive.
I saw a Cat on ebay and asked the seller to pass on my email to the buyer, to tell him to
not force the disk from the drive, because it would damage the head. I did not get to him
soon enough. He had already damaged the head. He said he'd wish he'd read my
message earlier.
This is such a common failure that I continue to warn people about it as often as I can. I
also did some repair for a fellow that used Cats in his business. I was only able to fix 2
of 5 drives. Luckily these had a head mount was just bent and not ripped off.
The desired fix is to open the disk drive and replace the nylon piece with something to
hold it in place. I used a piece of plastic but several use a small dab of JB Weld. There
is little reason to ever remove the rail.
The drive use is driven through a soldered on ribbon cable, unlike most such HD drives.
Because of software, it requires the DriveReady signal. Most drives no longer have this.
It can be created with the retriggerable oneshot, on an adapter cable.
I hope that covers it. Disassembly of the drive is a little trick to get at the rail but
anyone with some mechanical ability can do it. Do look at how the eject works before
disassembling.
Dwight
________________________________
From: Chris Hanson <cmhanson at eschatologist.net>
Sent: Sunday, January 24, 2021 3:13 PM
To: dwight <dkelvey at hotmail.com>; General Discussion: On-Topic and Off-Topic
Posts <cctalk at classiccmp.org>
Cc: Fred Cisin <cisin at xenosoft.com>
Subject: Re: personal history of personal computers
On Jan 4, 2021, at 1:31 PM, dwight via cctalk <cctalk at classiccmp.org> wrote:
There was a little known 68K machine. It was the Canon Cat. Although, it was generally
not intended as a development machine, in its short life, several applications were
developed.
It was primarily sold as a word processor ( quite powerful one at that ). It had Forth
running under the word processor. One could do both assembly and other things once one
understood how to access the Forth.
If you should ever get one, don't use the disk drive until you talk to me.
It has a common problem that if you don't understand it will destroy the drive.
What happens if it's not possible to talk to you? Can you write up just what the deal
is with the drive, so that everyone can learn?
-- Chris
1189
days inactive
1210
days old
22 comments
13 participants
participants (13)
-
bfranchuk＠jetnet.ab.ca -
billdegnan＠gmail.com -
cisin＠xenosoft.com -
cmhanson＠eschatologist.net -
dkelvey＠hotmail.com -
emu＠e-bbes.com -
glen.slick＠gmail.com -
lproven＠gmail.com -
mloewen＠cpumagic.scol.pa.us -
spectre＠floodgap.com -
stefan.skoglund＠agj.net -
toby＠telegraphics.com.au -
van.snyder＠sbcglobal.net